Investigation of optical bistability in core-shell nanoparticles consisting of nonlocal core and magnetoplasmonic shell

Abstract

We study the interaction of an electromagnetic field with a core-shell nanostructure and propose a nonlocal effective medium theory for a core-shell structure made of a nonlocal core and a magneto-optical shell cylinder embedded in the host medium. In addition to the appearance of optical bistability and tristability in this system, it is found that the threshold and window of bistability are strongly dependent on the nonlocality and magneto-optical properties of the core-shell nanoparticle, the size of the nanoparticle, and the incident wavelength. By fine modification of these parameters, it is possible to achieve maximal enhancement of optical nonlinearity from the proposed system. Our study offers a theoretical direction to further structure design and optimization and also applications in the high speed all-optical signal processing.